Potassium is needed to maintain good health. When potassium level falls below 3.5 mmol/L, Hypokalemia is diagnosed. In case of extremely low level of potassium (lower than 2.5 mmol/L) the following symptoms are appeared: malaise and fatigue. This low level of potassium can lead to severe muscle weakness and paralysis; respiratory failure; intermittent muscle spasms. It is known, foods that are good sources of potassium and low in sodium may reduce the risk of high blood pressure and stroke. Potassium supplementation is also recommended as an adjuvant antihypertensive agent for patients with essential hypertension.

Manganese Bromide is a highly water soluble crystalline salt composed of manganese and bromine with the formula MnBr2. Manganese Bromide can be used in place of palladium in the Stille reaction, which couples two carbon atoms using an organotin compound

Tetraamminecopper sulfate is a dark blue crystalline solid with a faint odor of ammonia. The primary hazard is the threat to the environment. Immediate steps should be taken to limit its spread to the environment. Used as a pesticide and fungicide, to print fabrics (especially in calico finishing), and to make other copper compounds.

Manganese Bromide is a highly water soluble crystalline salt composed of manganese and bromine with the formula MnBr2. Manganese Bromide can be used in place of palladium in the Stille reaction, which couples two carbon atoms using an organotin compound

Quinidine is a pharmaceutical agent that acts as a class I antiarrhythmic agent (Ia) in the heart. It is a stereoisomer of quinine, originally derived from the bark of the cinchona tree. The drug causes increased action potential duration, as well as a prolonged QT interval. Like all other class I antiarrhythmic agents, quinidine primarily works by blocking the fast inward sodium current (INa). Quinidine's effect on INa is known as a 'use-dependent block'. This means at higher heart rates, the block increases, while at lower heart rates, the block decreases. The effect of blocking the fast inward sodium current causes the phase 0 depolarization of the cardiac action potential to decrease (decreased Vmax). Quinidine also blocks the slowly inactivating, tetrodotoxin-sensitive Na current, the slow inward calcium current (ICA), the rapid (IKr) and slow (IKs) components of the delayed potassium rectifier current, the inward potassium rectifier current (IKI), the ATP-sensitive potassium channel (IKATP) and Ito. Quinidine is also an inhibitor of the cytochrome P450 enzyme 2D6 and can lead to increased blood levels of lidocaine, beta blockers, opioids, and some antidepressants. Quinidine also inhibits the transport protein P-glycoprotein and so can cause some peripherally acting drugs such as loperamide to have central nervous system side effects, such as respiratory depression if the two drugs are coadministered. Quinidine can cause thrombocytopenia, granulomatous hepatitis, myasthenia gravis, and torsades de pointes, so is not used much today. Torsades can occur after the first dose. Quinidine-induced thrombocytopenia (low platelet count) is mediated by the immune system and may lead to thrombocytic purpura. A combination of dextromethorphan and quinidine has been shown to alleviate symptoms of easy laughing and crying (pseudobulbar affect) in patients with amyotrophic lateral sclerosis and multiple sclerosis. This drug is marketed as Nuedexta in the United States. Intravenous quinidine is also indicated for the treatment of Plasmodium falciparum malaria. However, quinidine is not considered the first-line therapy for P. falciparum. The recommended treatments for P. falciparum malaria, according to the Toronto Notes 2008, are a combination of either quinine and doxycycline or atovaquone and proguanil (Malarone). The drug is also effective for the treatment of atrial fibrillation in horses.

Atropine inhibits the muscarinic actions of acetylcholine on structures innervated by postganglionic cholinergic nerves, and on smooth muscles which respond to endogenous acetylcholine but are not so innervated. As with other antimuscarinic agents, the major action of atropine is a competitive or surmountable antagonism which can be overcome by increasing the concentration of acetylcholine at receptor sites of the effector organ (e.g., by using anticholinesterase agents which inhibit the enzymatic destruction of acetylcholine). The receptors antagonized by atropine are the peripheral structures that are stimulated or inhibited by muscarine (i.e., exocrine glands and smooth and cardiac muscle). Responses to postganglionic cholinergic nerve stimulation also may be inhibited by atropine but this occurs less readily than with responses to injected (exogenous) choline esters. Atropine is relatively selective for muscarinic receptors. Its potency at nicotinic receptors is much lower, and actions at non-muscarinic receptors are generally undetectable clinically. Atropine does not distinguish among the M1, M2, and M3 subgroups of muscarinic receptors.

Pentaerythritol tetranitrate is an organic nitrate that has been used for the treatment of angina pectoris. Upon administration, the drug undergoes exstensive metabolism to NO which causes vasodilation and the relaxation of smooth muscle cells. The compound belongs to a familiy of explosive substances and may be used accordingly.

There is no information about biological and pharmacological application of Iron(II) fluoride (also known as ferrous fluoride). It is known, that this substance is used to catalyze some organic reactions.